Challenges associated with the separation of, or the recovery of, charged materials, including charged solid contaminants, in connection with aqueous systems, such as industrial process waters, are well known to those skilled in the art.
Historically, a variety of chemical treatments have been proposed for enhancing the settling of, or the filtration of, charged materials from aqueous media. In particular, adding a cationic flocculant to an aqueous media has long been used to enhance the dewatering of suspended solids that have an anionic character, such as in an activated sludge.
Such cationic flocculants often facilitate the agglomeration of solids suspended in the aqueous media, to form a distinct entity, referred to as floc, capable of being separated from at least a portion of the aqueous media. The use and development of synthetic polymers as cationic flocculants has continued to progress and evolve since their introduction several decades ago.
Thus, over the years certain cationic polymers have been suggested, or used as cationic flocculants for enhancing separation processes in such diverse applications as water treatment, papermaking, mineral processing, coal processing, petroleum recovery and refining, and many others. Included among such cationic polymers are the quaternary ammonium polymers of dialkyldiallyl ammonium compounds, e.g., DADMAC; polyethyleneimines; poly(meth) acrylamide/quaternary ammonium salt copolymers; polyamines and the epichlorohydrin functionalized polyalkylene polyamine condensates.
Notwithstanding the wide variety of these cationic flocculants, there remains a need for additional cationic polymers, in addition to the known materials identified above, to be used as cationic flocculants for enhancing separation processes, that have equal or better performance, that have a suitable long term stability, and/or that have suitable sensitivity to process variations, such as changes in temperature and alkalinity.